Simply explained rollers carry steel sheets through flames as hot as 1100º C and onto a cooling liquid bath. This compares to the typical temperature and length of time for hardening, while processes varies by industry, most steels are heat-treated at around 900 degrees Celsius for a few hours, while others are heated at similar temperatures for days.

Flash Bainite Processing. Click image for the largest view.

Cola’s Flash Bainite could enable automakers to build frames that are up to 30 percent thinner and lighter without compromising safety. Or, it could reinforce military armored vehicles without adding weight. New military designs could be safer and lighter becoming more fuel-efficient.

Cola is a self-taught metallurgist, and he wanted help to reveal the physics behind the process – to understand it in detail so that he could find ways to adapt it and even improve it.

He found a partnership with engineer Suresh Babu associate professor of materials science and engineering at Ohio State, and Director of the National Science Foundation Center for Integrative Materials Joining for Energy Applications at Ohio State. The deal provided research support for Brian Hanhold, who was an undergraduate student at the time who subsequently earned his master’s degree working out the answer and graduate student Tapasvi Lolla.

Babu remarks when inventor Gary Cola initially approached him, Babu didn’t know what to think, “The process that Gary described – it shouldn’t have worked,” he said. “I didn’t believe him. So he took my students and me to Detroit.”

Cola was claiming the new super steel was 7 percent stronger than martensitic advanced high-strength steel. [Martensitic steel is so named because the internal microstructure is entirely composed of a crystal form called martensite.] Cola further claimed that his steel could be drawn – that is, thinned and lengthened – 30 percent more than martensitic steels without losing its enhanced strength.

Lolla continues, “We asked for a few samples to test, and it turned out that everything he said was true. Then it was up to us to understand what was happening.”

Using an electron microscope, Hanhold and Lolla discovered that Cola’s process did indeed form martensite microstructure inside the steel. But they also saw another form called bainite microstructure, scattered with carbon-rich compounds called carbides.

Babu explains in more detail that in traditional, slow heat treatments, steel’s initial microstructure always dissolves into a homogeneous phase called austenite at peak temperature. But as the steel cools rapidly from this high temperature, all of the austenite normally transforms into martensite, “We think that, because this new process is so fast with rapid heating and cooling, the carbides don’t get a chance to dissolve completely within austenite at high temperature, so they remain in the steel and make this unique microstructure containing bainite martensite and carbides.”

Lolla points out that this unique microstructure boosts ductility – meaning that the steel can crumple a great deal before breaking – making it a potential impact-absorber for automotive applications.

Sharp readers might notice Hanhold isn’t a coauthor; he’s busy carrying his lessons into welding engineering. He hopes to solve the problem of heat-induced weakening during welding. High-strength steel often weakens just outside the weld joint, where the alloy has been heated and cooled. Hanhold suspects that bringing the speed of Cola’s method to welding might minimize the damage to adjacent areas and reduce the weakening. If successful, or dare we say when, another vast array of applications (particularly pipelines) will be substantially stronger and safer.

The Iron Age isn’t over yet. Steel has come a long way over the past century, the days of brittle steel such as that used to build the Titanic, which ended in the infamous disaster have been mostly resolved. But getting a few percent of improvement now is very important and a full 7 percent, a near revolution.

Steel performance is a crucial aspect of efficiency, wherever strength can gain and mass be reduced – consumers benefit and the fuel supply can be used to go further.

Congratulations to Mr. Gary Cola. We all hope your proceeds from licensing rewards you handsomely and your work continues to add value to our lives.

Comments

3 Comments so far

Musson on
June 14, 2011 7:18 AM

Here is an article about Starlite – a super plastic that can resist heat up to 2500 C. But, the inventor cannot seem to reach a deal with anyone.